FILE - In this July 29, 2011 file photo, Marine Corps Commandant Gen. James Amos speaks with reporters at Patuxent River Naval Air Station, Md. The Marine Corps commandant said Thursday Jan. 31, 2013, the infantry side is skeptical about how women will perform in those units and some positions may end up being closed if not enough females fail to meet the rigorous standards. (AP Photo/Cliff Owen, File)

FILE - In this Oct. 2, 1943, file photo, Marine Corps Women Reserves undergoing training at Camp Lejeune, New River, N.C., ride in a landing boat of the type that were used by the Marines in landing operations in the South Pacific. (AP Photo, File)

Members of the United States Marine Corps march during the 57th Presidential Inaugural Parade on Pennsylvania Avenue, Monday, Jan. 21, 2013 in Washington. Thousands marched during the 57th Presidential Inauguration parade after the ceremonial swearing-in of President Barack Obama. (AP Photo/Alex Brandon)

U.S. Marine Lance Corporal Carlos Lazano talks about a special training he underwent in which Marines were taught methods to "quiet the mind" and to reach an inner calm as a means to battle stress Tuesday Jan. 15, 2013 at Camp Pendlton, Calif. Marine Corps officials say they will build a curriculum that would integrate mindfulness-based techniques into their training if they see positive results from a pilot project. Mindfulness is a Buddhist-inspired concept that emphasizes active attention on the moment to keep the mind in the present. (AP Photo/Lenny Ignelzi)

U.S. Marine Lance Corporal Carlos Lazano talks about a special training he underwent in which Marines were taught methods to "quiet the mind" and to reach an inner calm as a means to battle stress Tuesday Jan. 15, 2013 at Camp Pendlton, Calif. Marine Corps officials say they will build a curriculum that would integrate mindfulness-based techniques into their training if they see positive results from a pilot project. Mindfulness is a Buddhist-inspired concept that emphasizes active attention on the moment to keep the mind in the present. (AP Photo/Lenny Ignelzi)

The U.S. Marine Corps version of Lockheed Martin's F35 Joint Strike Fighter, F-35B test aircraft BF-2 flies with external weapons for the first time over the Atlantic test range at Patuxent River Naval Air Systems Command in Maryland in a February 22, 2012 file photo. REUTERS/Lockheed Martin/Handout

U.S. President Barack Obama and first lady Michelle Obama visit military personnel and their families as they walk into Anderson Hall base chow hall at the Marine Corps Base Hawaii in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

U.S. President Barack Obama and first lady Michelle Obama visit military personnel and their families as they walk into Anderson Hall base chow hall at the Marine Corps Base Hawaii in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

U.S. President Barack Obama and first lady Michelle Obama visit military personnel and their families as they walk into Anderson Hall base chow hall at the Marine Corps Base Hawaii in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

Military personnel take pictures of U.S. President Barack Obama and first lady Michelle Obama as they greet military personnel and their families in Anderson Hall base chow hall at the Marine Corps Base Hawaii, in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

U.S. President Barack Obama and first lady Michelle Obama greet military personnel and their families as they walk into Anderson Hall base chow hall at the Marine Corps Base Hawaii, in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

U.S. President Barack Obama and first lady Michelle Obama visit military personnel and their families as they walk into Anderson Hall base chow hall at the Marine Corps Base Hawaii in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

Military personnel take pictures of U.S. President Barack Obama and first lady Michelle Obama as they greet military personnel and their families in Anderson Hall base chow hall at the Marine Corps Base Hawaii, in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing

U.S. President Barack Obama and first lady Michelle Obama greet military personnel and their families as they walk into Anderson Hall base chow hall at the Marine Corps Base Hawaii, in Kaneohe Bay, Hawaii December 25, 2012. REUTERS/Larry Downing